1. Field of the Invention
The present invention relates to a superfinishing machine for producing annular objects such as bearings.
2. Description of the Prior Art
Conventional superfinishing machines for producing annular objects are equipped with one honing stone and one shaft or finishing shaft. Therefore, several kinds of finishing machines are required for rough finishing and fine finishing of an annular workpiece using different kinds of honing stones. According to this conventional manner or producing annular objects, the annular workpiece must be transferred from the roughfinishing machine to the fine-finishing machine upon completion of rough finishing. However, during this transfer, the workpiece may be located out of position or alignment, thereby affecting accuracy in finishing. Such mis-location and mis-alignment have become serious problems since very great finishing accuracy has been required for some objects. For example, an accuracy of 1/100,000 mm has been demanded recently for some bearings.